In the electronic sensing market, there are a wide variety of sensors for sensing objects at a given location. Such sensors are configured to sense detectable and/or measurable characteristics of an object in order to sense the presence of an object near or about the sensor and other features and characteristics of the object being sensed. Such “sense characteristics” may include a variety of detectable characteristics, such as electronic, electromagnetic, ultrasonic, thermal, optical characteristics, among others.
Recent efforts have been made to incorporate sensors into the thin display panels of host devices. For example, efforts have been made to incorporate low profile finger print sensors into devices such as smart phones and computers (referred to generically as a “host device”) by incorporating that sensor into a glass panel, such as a display and/or interface panel of the device. Such sensors must be very thin and rigid so that they do not expand or contract differentially with respect to the glass panel, and the panel should have a smooth, continuous outer surface, even in the vicinity of the sensor. Current implementations are complex and expensive, typically requiring delicate silicon circuitry to be placed directly behind a chemically thinned or milled section of the host device cover.
Conventional methods include fingerprint sensors placed under the chemically strengthened glass used in modern electronic devices. However, these typically have degraded performance of the fingerprint sensor due to the thickness and the electrical properties of the glass. An alternative is to locally thin the glass in the area of the sensor. This is difficult to do at a low cost and weakens the mechanical robustness of an entire host device panel. Other methods include a wrapped fingerprint sensor assembly that can be integrated into a cutout in the host device panel. However, these designs have limitations in regards to the difficulties of integrating the wrapped sensor core into a low cost module using industry standard manufacturing processes.
To keep costs down, there is a need for a fingerprint sensor assembly that can be manufactured in high volumes in a cost-efficient manner. Ideally the sensor assembly should be a “module” that can be easily incorporated by a device manufacturer into the host device panel. In many smartphone designs, the resulting incorporated module becomes a “button” on the host device panel.
U.S. Provisional Application Nos. 62/258,284; 62/349,256; and 62/374,339, and U.S. Non-Provisional application Ser. No. 15/354,426 (U.S. Patent Application Publication No. 2017/0147852) “Electronic Sensor Supported on Rigid Substrate,” the respective disclosures of which are hereby incorporated by reference, describe “wrapped sensor” designs covered with a glass cover member. Such wrapped sensor designs comprise a rigid substrate wrapped in a flexible circuit subassembly comprising conductive traces, a circuit element such as an integrated circuit or application specific integrated circuit (“ASIC”), and conductive interconnects connecting the traces to the circuit element all disposed on a flexible substrate material.
U.S. Provisional Application No. 62/354,210, U.S. Non-Provisional application Ser. No. 15/628,003 (U.S. Patent Application Publication No. 2017-0372112) “Reinforcement Panel for Fingerprint Sensor Cover” the disclosure of which is hereby incorporated by reference, describes “wrapped sensor” designs covered with a glass cover member reinforced with a ceramic layer to enhance robustness of the installed sensor assembly.
U.S. Provisional Application No. 62/382,864, U.S. Non-Provisional application Ser. No. 15/693,882 “Method of Securing a Fingerprint Sensor onto a Glass Cover Member Incorporated within a Glass Cover of a Mobile Device” the disclosure of which is hereby incorporated by reference, describes a method that can be used to secure the fingerprint sensor assembly disclosed in the current application onto a cover panel.
U.S. Provisional Application No. 62/382,884, U.S. Non-Provisional application Ser. No. 15/693,817 “Method of Manufacturing a Cover Member Suitable for a Fingerprint Sensor” the disclosure of which is hereby incorporated by reference, describes a method of manufacturing a cover panel suitable for being attached to the fingerprint sensor assembly described in the current application.